<feed xmlns='http://www.w3.org/2005/Atom'>
<title>litmus-rt.git/arch/avr32/include/uapi/asm, branch master</title>
<subtitle>The LITMUS^RT kernel.</subtitle>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/'/>
<entry>
<title>avr32: wire up missing syscalls</title>
<updated>2015-02-09T14:27:44+00:00</updated>
<author>
<name>Hans-Christian Egtvedt</name>
<email>egtvedt@samfundet.no</email>
</author>
<published>2014-12-25T18:58:50+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=f3240c1f6d18591b2c1ef33ed18d5ca91e62c104'/>
<id>f3240c1f6d18591b2c1ef33ed18d5ca91e62c104</id>
<content type='text'>
This patch adds a bunch of missing syscalls to AVR32:
__NR_pread64
__NR_pwrite64
__NR_timerfd_create
__NR_fallocate
__NR_timerfd_settime
__NR_timerfd_gettime
__NR_signalfd4
__NR_eventfd2
__NR_epoll_create1
__NR_dup3
__NR_pipe2
__NR_inotify_init1
__NR_preadv
__NR_pwritev
__NR_rt_tgsigqueueinfo
__NR_perf_event_open
__NR_recvmmsg
__NR_fanotify_init
__NR_fanotify_mark
__NR_prlimit64
__NR_name_to_handle_at
__NR_open_by_handle_at
__NR_clock_adjtime
__NR_syncfs
__NR_sendmmsg
__NR_process_vm_readv
__NR_process_vm_writev
__NR_kcmp
__NR_finit_module
__NR_sched_setattr
__NR_sched_getattr
__NR_renameat2
__NR_seccomp
__NR_getrandom
__NR_memfd_create
__NR_bpf
__NR_execveat

On AVR32, all parameters beyond the 5th are passed on the stack. System
calls don't use the stack -- they borrow a callee-saved register
instead. This means that syscalls that take 6 parameters must be called
through a stub that pushes the last parameter on the stack.

This relates to syscall fallocate, fanotify_mark, process_vm_readv, and
process_vm_writev.

Signed-off-by: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch adds a bunch of missing syscalls to AVR32:
__NR_pread64
__NR_pwrite64
__NR_timerfd_create
__NR_fallocate
__NR_timerfd_settime
__NR_timerfd_gettime
__NR_signalfd4
__NR_eventfd2
__NR_epoll_create1
__NR_dup3
__NR_pipe2
__NR_inotify_init1
__NR_preadv
__NR_pwritev
__NR_rt_tgsigqueueinfo
__NR_perf_event_open
__NR_recvmmsg
__NR_fanotify_init
__NR_fanotify_mark
__NR_prlimit64
__NR_name_to_handle_at
__NR_open_by_handle_at
__NR_clock_adjtime
__NR_syncfs
__NR_sendmmsg
__NR_process_vm_readv
__NR_process_vm_writev
__NR_kcmp
__NR_finit_module
__NR_sched_setattr
__NR_sched_getattr
__NR_renameat2
__NR_seccomp
__NR_getrandom
__NR_memfd_create
__NR_bpf
__NR_execveat

On AVR32, all parameters beyond the 5th are passed on the stack. System
calls don't use the stack -- they borrow a callee-saved register
instead. This means that syscalls that take 6 parameters must be called
through a stub that pushes the last parameter on the stack.

This relates to syscall fallocate, fanotify_mark, process_vm_readv, and
process_vm_writev.

Signed-off-by: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: sock: allow eBPF programs to be attached to sockets</title>
<updated>2014-12-06T05:47:32+00:00</updated>
<author>
<name>Alexei Starovoitov</name>
<email>ast@plumgrid.com</email>
</author>
<published>2014-12-01T23:06:35+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=89aa075832b0da4402acebd698d0411dcc82d03e'/>
<id>89aa075832b0da4402acebd698d0411dcc82d03e</id>
<content type='text'>
introduce new setsockopt() command:

setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &amp;prog_fd, sizeof(prog_fd))

where prog_fd was received from syscall bpf(BPF_PROG_LOAD, attr, ...)
and attr-&gt;prog_type == BPF_PROG_TYPE_SOCKET_FILTER

setsockopt() calls bpf_prog_get() which increments refcnt of the program,
so it doesn't get unloaded while socket is using the program.

The same eBPF program can be attached to multiple sockets.

User task exit automatically closes socket which calls sk_filter_uncharge()
which decrements refcnt of eBPF program

Signed-off-by: Alexei Starovoitov &lt;ast@plumgrid.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
introduce new setsockopt() command:

setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &amp;prog_fd, sizeof(prog_fd))

where prog_fd was received from syscall bpf(BPF_PROG_LOAD, attr, ...)
and attr-&gt;prog_type == BPF_PROG_TYPE_SOCKET_FILTER

setsockopt() calls bpf_prog_get() which increments refcnt of the program,
so it doesn't get unloaded while socket is using the program.

The same eBPF program can be attached to multiple sockets.

User task exit automatically closes socket which calls sk_filter_uncharge()
which decrements refcnt of eBPF program

Signed-off-by: Alexei Starovoitov &lt;ast@plumgrid.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: introduce SO_INCOMING_CPU</title>
<updated>2014-11-11T18:00:06+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2014-11-11T13:54:28+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=2c8c56e15df3d4c2af3d656e44feb18789f75837'/>
<id>2c8c56e15df3d4c2af3d656e44feb18789f75837</id>
<content type='text'>
Alternative to RPS/RFS is to use hardware support for multiple
queues.

Then split a set of million of sockets into worker threads, each
one using epoll() to manage events on its own socket pool.

Ideally, we want one thread per RX/TX queue/cpu, but we have no way to
know after accept() or connect() on which queue/cpu a socket is managed.

We normally use one cpu per RX queue (IRQ smp_affinity being properly
set), so remembering on socket structure which cpu delivered last packet
is enough to solve the problem.

After accept(), connect(), or even file descriptor passing around
processes, applications can use :

 int cpu;
 socklen_t len = sizeof(cpu);

 getsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &amp;cpu, &amp;len);

And use this information to put the socket into the right silo
for optimal performance, as all networking stack should run
on the appropriate cpu, without need to send IPI (RPS/RFS).

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Alternative to RPS/RFS is to use hardware support for multiple
queues.

Then split a set of million of sockets into worker threads, each
one using epoll() to manage events on its own socket pool.

Ideally, we want one thread per RX/TX queue/cpu, but we have no way to
know after accept() or connect() on which queue/cpu a socket is managed.

We normally use one cpu per RX queue (IRQ smp_affinity being properly
set), so remembering on socket structure which cpu delivered last packet
is enough to solve the problem.

After accept(), connect(), or even file descriptor passing around
processes, applications can use :

 int cpu;
 socklen_t len = sizeof(cpu);

 getsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &amp;cpu, &amp;len);

And use this information to put the socket into the right silo
for optimal performance, as all networking stack should run
on the appropriate cpu, without need to send IPI (RPS/RFS).

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: introduce SO_BPF_EXTENSIONS</title>
<updated>2014-01-19T03:08:58+00:00</updated>
<author>
<name>Michal Sekletar</name>
<email>msekleta@redhat.com</email>
</author>
<published>2014-01-17T16:09:45+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=ea02f9411d9faa3553ed09ce0ec9f00ceae9885e'/>
<id>ea02f9411d9faa3553ed09ce0ec9f00ceae9885e</id>
<content type='text'>
For user space packet capturing libraries such as libpcap, there's
currently only one way to check which BPF extensions are supported
by the kernel, that is, commit aa1113d9f85d ("net: filter: return
-EINVAL if BPF_S_ANC* operation is not supported"). For querying all
extensions at once this might be rather inconvenient.

Therefore, this patch introduces a new option which can be used as
an argument for getsockopt(), and allows one to obtain information
about which BPF extensions are supported by the current kernel.

As David Miller suggests, we do not need to define any bits right
now and status quo can just return 0 in order to state that this
versions supports SKF_AD_PROTOCOL up to SKF_AD_PAY_OFFSET. Later
additions to BPF extensions need to add their bits to the
bpf_tell_extensions() function, as documented in the comment.

Signed-off-by: Michal Sekletar &lt;msekleta@redhat.com&gt;
Cc: David Miller &lt;davem@davemloft.net&gt;
Reviewed-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For user space packet capturing libraries such as libpcap, there's
currently only one way to check which BPF extensions are supported
by the kernel, that is, commit aa1113d9f85d ("net: filter: return
-EINVAL if BPF_S_ANC* operation is not supported"). For querying all
extensions at once this might be rather inconvenient.

Therefore, this patch introduces a new option which can be used as
an argument for getsockopt(), and allows one to obtain information
about which BPF extensions are supported by the current kernel.

As David Miller suggests, we do not need to define any bits right
now and status quo can just return 0 in order to state that this
versions supports SKF_AD_PROTOCOL up to SKF_AD_PAY_OFFSET. Later
additions to BPF extensions need to add their bits to the
bpf_tell_extensions() function, as documented in the comment.

Signed-off-by: Michal Sekletar &lt;msekleta@redhat.com&gt;
Cc: David Miller &lt;davem@davemloft.net&gt;
Reviewed-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>avr32: uapi: be sure of "_UAPI" prefix for all guard macros</title>
<updated>2013-11-20T08:53:22+00:00</updated>
<author>
<name>Chen Gang</name>
<email>gang.chen@asianux.com</email>
</author>
<published>2013-11-12T08:38:47+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=e7f2c8c1f0e5b062c23001dac229e570228940e8'/>
<id>e7f2c8c1f0e5b062c23001dac229e570228940e8</id>
<content type='text'>
For all uapi headers, need use "_UAPI" prefix for its guard macro
(which will be stripped by "scripts/headers_installer.sh").

Also remove redundant files (bitsperlong.h, errno.h, fcntl.h, ioctl.h,
ioctls.h, ipcbuf.h, kvm_para.h, mman.h, poll.h, resource.h, siginfo.h,
statfs.h, and unistd.h) which are already in Kbuild.

Also be sure that all "#endif" only have one empty line above, and each
file has guard macro.

Signed-off-by: Chen Gang &lt;gang.chen@asianux.com&gt;
Signed-off-by: Hans-Christian Egtvedt &lt;hegtvedt@cisco.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For all uapi headers, need use "_UAPI" prefix for its guard macro
(which will be stripped by "scripts/headers_installer.sh").

Also remove redundant files (bitsperlong.h, errno.h, fcntl.h, ioctl.h,
ioctls.h, ipcbuf.h, kvm_para.h, mman.h, poll.h, resource.h, siginfo.h,
statfs.h, and unistd.h) which are already in Kbuild.

Also be sure that all "#endif" only have one empty line above, and each
file has guard macro.

Signed-off-by: Chen Gang &lt;gang.chen@asianux.com&gt;
Signed-off-by: Hans-Christian Egtvedt &lt;hegtvedt@cisco.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: introduce SO_MAX_PACING_RATE</title>
<updated>2013-09-28T22:35:41+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2013-09-24T15:20:52+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=62748f32d501f5d3712a7c372bbb92abc7c62bc7'/>
<id>62748f32d501f5d3712a7c372bbb92abc7c62bc7</id>
<content type='text'>
As mentioned in commit afe4fd062416b ("pkt_sched: fq: Fair Queue packet
scheduler"), this patch adds a new socket option.

SO_MAX_PACING_RATE offers the application the ability to cap the
rate computed by transport layer. Value is in bytes per second.

u32 val = 1000000;
setsockopt(sockfd, SOL_SOCKET, SO_MAX_PACING_RATE, &amp;val, sizeof(val));

To be effectively paced, a flow must use FQ packet scheduler.

Note that a packet scheduler takes into account the headers for its
computations. The effective payload rate depends on MSS and retransmits
if any.

I chose to make this pacing rate a SOL_SOCKET option instead of a
TCP one because this can be used by other protocols.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Steinar H. Gunderson &lt;sesse@google.com&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As mentioned in commit afe4fd062416b ("pkt_sched: fq: Fair Queue packet
scheduler"), this patch adds a new socket option.

SO_MAX_PACING_RATE offers the application the ability to cap the
rate computed by transport layer. Value is in bytes per second.

u32 val = 1000000;
setsockopt(sockfd, SOL_SOCKET, SO_MAX_PACING_RATE, &amp;val, sizeof(val));

To be effectively paced, a flow must use FQ packet scheduler.

Note that a packet scheduler takes into account the headers for its
computations. The effective payload rate depends on MSS and retransmits
if any.

I chose to make this pacing rate a SOL_SOCKET option instead of a
TCP one because this can be used by other protocols.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Steinar H. Gunderson &lt;sesse@google.com&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: rename busy poll socket op and globals</title>
<updated>2013-07-11T00:08:27+00:00</updated>
<author>
<name>Eliezer Tamir</name>
<email>eliezer.tamir@linux.intel.com</email>
</author>
<published>2013-07-10T14:13:36+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=64b0dc517ea1b35d02565a779e6cb77ae9045685'/>
<id>64b0dc517ea1b35d02565a779e6cb77ae9045685</id>
<content type='text'>
Rename LL_SO to BUSY_POLL_SO
Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll}
Fix up users of these variables.
Fix documentation for sysctl.

a patch for the socket.7  man page will follow separately,
because of limitations of my mail setup.

Signed-off-by: Eliezer Tamir &lt;eliezer.tamir@linux.intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rename LL_SO to BUSY_POLL_SO
Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll}
Fix up users of these variables.
Fix documentation for sysctl.

a patch for the socket.7  man page will follow separately,
because of limitations of my mail setup.

Signed-off-by: Eliezer Tamir &lt;eliezer.tamir@linux.intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: add socket option for low latency polling</title>
<updated>2013-06-17T22:48:14+00:00</updated>
<author>
<name>Eliezer Tamir</name>
<email>eliezer.tamir@linux.intel.com</email>
</author>
<published>2013-06-14T13:33:57+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=dafcc4380deec21d160c31411f33c8813f67f517'/>
<id>dafcc4380deec21d160c31411f33c8813f67f517</id>
<content type='text'>
adds a socket option for low latency polling.
This allows overriding the global sysctl value with a per-socket one.
Unexport sysctl_net_ll_poll since for now it's not needed in modules.

Signed-off-by: Eliezer Tamir &lt;eliezer.tamir@linux.intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
adds a socket option for low latency polling.
This allows overriding the global sysctl value with a per-socket one.
Unexport sysctl_net_ll_poll since for now it's not needed in modules.

Signed-off-by: Eliezer Tamir &lt;eliezer.tamir@linux.intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>avr32: fix building warnings caused by redefinitions of HZ</title>
<updated>2013-05-22T19:05:44+00:00</updated>
<author>
<name>Jiang Liu</name>
<email>liuj97@gmail.com</email>
</author>
<published>2013-05-17T15:45:18+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=0c9b5a317b8ae7201fed07ec66d642b2ad7ea1b0'/>
<id>0c9b5a317b8ae7201fed07ec66d642b2ad7ea1b0</id>
<content type='text'>
As suggested by David Howells &lt;dhowells@redhat.com&gt;, use
asm-generic/param.h and uapi/asm-generic/param.h for AVR32.

It also fixes building warnings caused by redefinitions of HZ:
In file included from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:6:1: warning: "HZ" redefined
In file included from /ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:4,
                 from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/uapi/asm/param.h:6:1: warning: this is the location of the previous definition

Signed-off-by: Jiang Liu &lt;jiang.liu@huawei.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As suggested by David Howells &lt;dhowells@redhat.com&gt;, use
asm-generic/param.h and uapi/asm-generic/param.h for AVR32.

It also fixes building warnings caused by redefinitions of HZ:
In file included from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:6:1: warning: "HZ" redefined
In file included from /ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:4,
                 from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/uapi/asm/param.h:6:1: warning: this is the location of the previous definition

Signed-off-by: Jiang Liu &lt;jiang.liu@huawei.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: add option to enable error queue packets waking select</title>
<updated>2013-03-31T23:44:20+00:00</updated>
<author>
<name>Keller, Jacob E</name>
<email>jacob.e.keller@intel.com</email>
</author>
<published>2013-03-28T11:19:25+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=7d4c04fc170087119727119074e72445f2bb192b'/>
<id>7d4c04fc170087119727119074e72445f2bb192b</id>
<content type='text'>
Currently, when a socket receives something on the error queue it only wakes up
the socket on select if it is in the "read" list, that is the socket has
something to read. It is useful also to wake the socket if it is in the error
list, which would enable software to wait on error queue packets without waking
up for regular data on the socket. The main use case is for receiving
timestamped transmit packets which return the timestamp to the socket via the
error queue. This enables an application to select on the socket for the error
queue only instead of for the regular traffic.

-v2-
* Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file
* Modified every socket poll function that checks error queue

Signed-off-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Cc: Jeffrey Kirsher &lt;jeffrey.t.kirsher@intel.com&gt;
Cc: Richard Cochran &lt;richardcochran@gmail.com&gt;
Cc: Matthew Vick &lt;matthew.vick@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, when a socket receives something on the error queue it only wakes up
the socket on select if it is in the "read" list, that is the socket has
something to read. It is useful also to wake the socket if it is in the error
list, which would enable software to wait on error queue packets without waking
up for regular data on the socket. The main use case is for receiving
timestamped transmit packets which return the timestamp to the socket via the
error queue. This enables an application to select on the socket for the error
queue only instead of for the regular traffic.

-v2-
* Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file
* Modified every socket poll function that checks error queue

Signed-off-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Cc: Jeffrey Kirsher &lt;jeffrey.t.kirsher@intel.com&gt;
Cc: Richard Cochran &lt;richardcochran@gmail.com&gt;
Cc: Matthew Vick &lt;matthew.vick@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
